Increase or remove sidebarDepth limit for deeply nested page structures

[philsv]

Description

Currently, the sidebarDepth prop on EvidenceDefaultLayout has a maximum effective value of 3, limiting sidebar navigation to 3 levels of nested pages. For projects with more complex information architectures, this restriction forces compromises in URL structure or requires workarounds.

Problem

When organizing content into a logical hierarchy that exceeds 3 levels, the sidebar navigation stops displaying nested items beyond that depth. This creates a disconnect between the URL structure and the navigation UI.

Users navigating to level 4+ pages have no sidebar visibility of where they are in the hierarchy, making navigation difficult.

Proposed Solution

Increase the default maximum from 3 to 6 or higher
Or make it unlimited by default, letting users set a lower value if they want to collapse deep structures
Add a "show more" expander for deep hierarchies that exceed the configured depth

What problem would this solve?

Navigation visibility for deep content hierarchies

How should it work?

Update core-components package:

<!-- Line 22: Default depth is 3 -->
export let sidebarDepth = 3;

<!-- Line 210 & 331: Only shows 3rd level if sidebarDepth > 2 -->
{#if secondLevelFile.children.length > 0 && sidebarDepth > 2}
    {#each secondLevelFile.children as thirdLevelFile}
        <!-- renders 3rd level -->
    {/each}
{/if}

To support deeper nesting, Evidence would need to:

1. Replace the hardcoded nested loops with a recursive component
2. Pass sidebarDepth to control how deep the recursion goes

This is a more significant architectural change than just increasing a number - the entire sidebar rendering logic would need refactoring.

Ideal would be:

<EvidenceDefaultLayout 
  data={data} 
  sidebarDepth={6} <- up to 6 or higher
  sidebarCollapsible={true}
>